A Thermoelectric Bracelet To Maintain a Comfortable Body Temperature

rtoz writes "Heating or cooling certain parts of your body — such as applying a warm towel to your forehead if you feel chilly — can help maintain your perceived thermal comfort. Using that concept, four MIT engineering students developed a thermoelectric bracelet that monitors air and skin temperature, and sends tailored pulses of hot or cold waveforms to the wrist to help maintain thermal comfort. The product is now a working prototype. And although people would use the device for personal comfort, the team says the ultimate aim is to reduce the energy consumption of buildings, by cooling and heating the individual — not the building. The team estimates that if the device stops one building from adjusting its temperature by even just 1 degree Celsius, it will save roughly 100 kilowatt-hours per month."

Comments

BEYAR !!

[Anonymous Coward]

Oy !!

What about the humidity?

[Bill_the_Engineer]

Personal comfort involves more than just temperature.

Re:What about the humidity?

[MightyYar]

And 1 degree C is pretty cold... ~

Re:What about the humidity?

[fuzzyfuzzyfungus]

Any AC/Climate Control people know how the energy costs of modifying humidity compare to those of modifying temperature?

For weedy little freestanding units, dehumidifiers appear to be pretty close to air conditioners that blow warm exhaust air in your face rather than outside; but there may be greater economies to be had in some mechanisms that only work on a larger scale, or when built into the building from day one, or so forth.

Re:What about the humidity?

[MightyYar]

At my office, we are all required to inhale the office air, but exhale through little snorkels placed throughout the office which exhaust to the outside.

Re:What about the humidity?

[Anonymous Coward]

You're right; they should just give up because their idea does not simultaneously solve every problem that affects personal comfort. We should have more people like you around -- we'd put an end to all these half-measure solutions we've implemented and we'd be living in a utopia, because the only single thing we'd ever have done would have been to implement the uber-solution to all possible problems!

Re:What about the humidity?

[fuzzyfuzzyfungus]

A man's body is his own. His water belongs to the corporation.

Re:What about the humidity?

[K. S. Kyosuke]

The next version will include a small water tank with a sprinkler and a miniature hair-dryer.

Re:What about the humidity?

[JWW]

Damn, wish I had mod points....

Re:What about the humidity?

[Anonymous Coward]

Hey, I'm AC. I've found that a pot of boiling water on the kitchen stove in the winter lets me keep my thermostat 3 degrees F lower and have the same apparent temperature. OTOH, in Arizona where the air is bone-dry they don't use many air conditioners, they have "swamp coolers" that lower the temperature by forcing air through a stream of water; the evaporating water cools the air. It's a lot cheaper since there's no compressor, but it won't work in many other places.

Re:What about the humidity?

[dj245]

Any AC/Climate Control people know how the energy costs of modifying humidity compare to those of modifying temperature? For weedy little freestanding units, dehumidifiers appear to be pretty close to air conditioners that blow warm exhaust air in your face rather than outside; but there may be greater economies to be had in some mechanisms that only work on a larger scale, or when built into the building from day one, or so forth.

At my old house (with central AC) I purchased a fancy thermostat with 7 day programming, 4 programming points per day, and the ability to take several remote temperature measurements and average them.

Another feature it had was "humidity control". You could make a setpoint for humidity, and the AC would come on every now and then to maintain that humidity level. Temperature might have been 78F but with reduced humidity it was quite comfortable.

Re:What about the humidity?

[Anonymous Coward]

If these were for "personal comfort" in a work environment then humidity is a big factor to comfort.

Not to mention this is NOT A NEW IDEA. Of course MIT has a habit of reinventing shit and claiming it as their own discovery.

Re:What about the humidity?

[jbengt]

Any AC/Climate Control people know how the energy costs of modifying humidity compare to those of modifying temperature?

Depends on how you do it, of course.

The typical pre-energy codes way was to cool the air below the dewpoint with a regular A/C cycle then reheat using electric heat (or another heat source, if readily available). That is very cheap to install but very energy-intensive.

The "weedy little freestanding units" do essentially the same thing, but use the hot gas from the compressor to reheat the air. This doesn't cost much more to install (the refrigeration controls used to be the tricky part) and uses a little less energy than regular air conditioning that rejects the heat to outdoors because of the lower condensing temperatures. Larger packaged A/C systems can usually provide this as an option, but the extra cost is not often spent. (Most of the hours needing dehumidification need cooling too, so why add reheat for those few hours a year when it's 75F and raining?)

More sophisticated systems use dessicants to dry the air, which is regenerated by passing exhaust air across the dessicant and/or heating it. This uses very little energy, but is pretty pricy to install. Still, it's a popular choice as part of a "energy recovery" systems for those wishing to score energy efficiency points.

Re:What about the humidity?

[chuckinator]

A man's body is his own. His water belongs to the sietch.

Fixed that for you.

Re: What about the humidity?

[jd2112]

You work for a company on Arrakkis?

Re:What about the humidity?

[jbengt]

One other thing.
You can improve dehumidification somewhat just by reducing the air flow of the A/C unit. You get a little less cooling, requiring the A/C to run longer, and reduce the temperature of the air significantly further below the dewpoint, ringing more moisture out. Of course, you can only go so far before running into problems so like freezing the coil or shutting down on safeties (if they're there), so YMMV.

Re:What about the humidity?

[Hognoxious]

You must be a hoot at parties. Theoretically speaking, of course.

Re:What about the humidity?

[chuckinator]

Yes, I wear my owl costume to them.

Re:What about the humidity?

[Flere Imsaho]

A man's body is his own. His water belongs to the corporation.

Spice is a hell of a drug.

Re:What about the humidity?

[Grishnakh]

OTOH, in Arizona where the air is bone-dry they don't use many air conditioners, they have "swamp coolers" that lower the temperature by forcing air through a stream of water

You've obviously not been to Arizona in at least 20 years. No one uses swamp coolers any more because they don't work when the temperature is too high or the weather too humid. You'll see some older houses (70s-80s) that have piggyback swamp coolers + heatpumps, but no one builds houses like that any more, they've all gone to regular heat pumps because the efficiency is high on modern units, and again, swamp coolers stop working when it's too hot, and these days, it's gotten extremely hot in Phoenix and it never goes below 100 in the summer, even at night.

Re:What about the humidity?

[Anonymous Coward]

Fuck that guy. Just have Stilgar shank him with his crysknife.

Re:What about the humidity?

[RockDoctor]

Harry Harrison?

Sold!

[i kan reed]

Give one to me to keep cool, one to my girlfriend to keep warm, and we'll set the AC in the middle.

Re:Sold!

[Anonymous Coward]

You're assuming it's equally efficient to heat or cool a space. It is much more energy intensive to cool a space by 1 than it is to heat the same space by the same amount, thermodynamics and all.

Re:Sold!

[Penguinisto]

Wait until she hits menopause... then you'll have to swap out that AC unit for a ginormous pile of dry ice.

Re:Sold!

[icebike]

Well, it actually is the same amount of energy transfer, its just that our cooling systems aren't as efficient as our heating systems.

Re:Sold!

[Anonymous Coward]

Give me your girlfriend to keep me warm and we'll be all set :D

Re:Sold!

[Anonymous Coward]

If that was true, then heat-pumps for home heating woudn't exist.

Re:Sold!

[Anonymous Coward]

Give one to me to keep cool, one to my girlfriend to keep warm, and we'll set the AC in the middle.

That sounds sexy
-A threesomely AC ;)

Re:Sold!

[viperidaenz]

Just inflate her with warm air.

Re:Sold!

[viperidaenz]

It is true and they do exist.
When a heat pump cools a room, the fan generates heat inside the room and the compressor generates heat outside next to the radiator.
The coolant also experiences friction as it moves through the pipes.

When you're heating a room, that heat, which still lowers efficiency, still adds to the net outcome - the room gets hot. When cooling that heat requires the heat pump to work hard for the same net result.

Waveforms?

[fiannaFailMan]

Quoth TFA:

sends tailored pulses of hot or cold waveforms to the wrist to help maintain thermal comfort

"Waveforms?" What does that mean? Does it work by convection, conduction, radiation or what?

Personally I like the little space heater I keep under my desk. Makes it nice and cozy in winter. Much nicer than wrapping up with more layers.

Re:Waveforms?

[RealGene]

Thermoelectric coolers are typically controlled with PWM, to adjust their temperature. The polarity determines which direction the heat is pumped, the duty cycle of the PWM determines how much.

Re:Waveforms?

[fuzzyfuzzyfungus]

I assume that 'waveforms' is a poorly-written-up allusion to the fact that a peltier element (while most usually driven in one direction for its entire life, or, as with those cheapie 'car fridge' units that plug into the DC jack and keep your no-it-isn't-beer-officer-it's-refreshing-soda cool; but can also warm things, flicked between running in one direction and running in the other quite infrequently) is a device that you would treat as demanding specially crafted AC current for a project like this.

Because user temperature and ambient temperature can both vary, sometimes fairly quickly(metabolic exertion, user enters a sunlit office from an interior corridor, whatever), the system would need to be able to drive the peltier in either direction at short notice: to warm the user, drive so that the hot side is coupled to the major blood vessels in the wrist, to cool them, drive in reverse with the hot side dumping to a heat sink(which, given the miserable efficiency of peltiers, will be a little tricky to mount comfortably on the wrist. Liquid coolant circulating through a tube in the sleeve would be convenient; but start to get into 'uncomfortable cyborg' territory pretty quickly. At any given moment, the Peltier would be an essentially DC device (unlike capacitors or inductors/magnetics in general, they don't depend on either DC ripple or AC current to do anything special); but the driver would have to be able to switch V+ and ground(as well as either the magnitude of V+ or the amount of current allowed to flow) swiftly and automatically in response to sensor inputs.

Re:Waveforms?

[icebike]

Once your follow the link from the self promoting blog to the actual article from MIT you find this

Over the course of developing its technology, the Wristify team made a key discovery: Human skin is very sensitive to minute, rapid changes in temperature, which affect the whole body. They found they needed to heat or cool any body part (in their case, the wrist) at a rate of at least 0.1 C per second in order to make the entire body, overall, feel several degrees warmer or colder.

After 15 prototypes, the team landed on its final product, which resembles a wristwatch and can be powered, for up to eight hours, by a lithium polymer battery. This prototype demonstrated a rate of change of up to 0.4 C per second.

The “watch” part of the prototype actually consists of the team’s custom copper-alloy-based heat sink (a component that lowers a device’s temperature by dissipating heat). Attached is an automated control system that manages the intensity and duration of the thermal pulses delivered to the heat sink. Integrated thermometers also measure external and body temperature to adjust accordingly.

Its clear from the article that there is no actual heating of the body involved. Their system does not have enough power to heat 150 pounds of (essentially) water even one degree in the time period mentioned, let alone maintain any elevated temperature over 8 hours.

They are simply tricking the body into thinking it is warm enough or cool enough so that you don't FEEL cold / hot. You still actually ARE too cold or too hot.

This sounds interesting but I wonder just how safe it is to trick the body's thermal regulation its cool enough such that it no longer pays attention to the fact that it might be running dangerously close to heat induced stroke? Or trick it into thinking its cold, so it ramps up the metabolism.

In fact this might be a more useful as w weight loss device than an energy saving device.
But I'm still not convinced we should let engineers start micromanaging bodily functions, when all they are worried about is the device and the energy consumption.

Technology to do the same thing was invented a LONG time ago. Its called a sweater.

Even cheaper is a simple cap. Put it on, and you reduce heat loss through your head sufficiently enough to actually warm your entire body. Take it off and the reverse happens. The cap will last for years with no need for environment polluting batteries, and never has to be plugged in or recharged.

Re:Waveforms?

[chuckinator]

The thermoelectric elements work by the Peltier Effect. They're not as efficient as cartridge heating elements for heating or vapor compression refrigeration for cooling, but they also don't require moving parts and can be use in places where either of the more efficient mechanisms can't (like pressed against a gel pad pressed against a human body). They're a polarized device that pushes heat in one direction with current flowing in one direction and pushes heat in the opposite direction with an opposite electrical polarity.

Re:Waveforms?

[tompaulco]

Personally I like the little space heater I keep under my desk. Makes it nice and cozy in winter. Much nicer than wrapping up with more layers.

Yes, I would like to have one of those, too, but our office manager forbids it. Which is a shame because my office is on an outside wall and it is regularly 62 degrees Fahrenheit on mornings that are chilly outside, then by the afternoon, it is usually about 85 degrees.

Re:Waveforms?

[Anonymous Coward]

Technology to do the same thing was invented a LONG time ago. Its called a sweater.

Or at the other end of the scale, Nudism!

Re:Waveforms?

[The_Wilschon]

You sound like Ebenezer Scrooge: http://youtu.be/QIcoa0oI5Cc?t=10s

It's not a favorable comparison.

Re:Waveforms?

[Anonymous Coward]

But I'm still not convinced we should let engineers start micromanaging bodily functions, when all they are worried about is the device and the energy consumption.

It can't be all bad, for every electric shock to make someone pee their pants, there's bound to be a different shock to get me to stand every now and then as I'm playing WoW in the basement. I don't want to end up like this guy or this guy, after all.

Re:Waveforms?

[Grishnakh]

Yes, I had the same problem at a past job. That's why you put your space heater under your desk. Does your office manager run around looking under everyone's desk every day?

Re:Waveforms?

[Anonymous Coward]

Personally I like the little space heater I keep under my desk. Makes it nice and cozy in winter. Much nicer than wrapping up with more layers.

Yes, I would like to have one of those, too, but our office manager forbids it. Which is a shame because my office is on an outside wall and it is regularly 62 degrees Fahrenheit on mornings that are chilly outside, then by the afternoon, it is usually about 85 degrees.

Get a heated foot rest, take off your shoes and pop them on there. Amazon sells them, $40 or so, it only takes 50-100 watts so no breaker tripping worries for the office/IT manager. Worked wonders for me in cold winter, much better than the radiant heat panel. Bonus, no super dry air issues from an actual space heater.

Re:Waveforms?

[Anonymous Coward]

AMD or Intel?

At least one fancy house that won some architectural award here in London credits space heating to Apple Computers.

Re:Waveforms?

[mattack2]

They are simply tricking the body into thinking it is warm enough or cool enough so that you don't FEEL cold / hot. You still actually ARE too cold or too hot.

I thought this was obvious just from the summary.

But yes, I too was wondering about this from a weight loss perspective. I've always wondered if you could make your body "think" it's too cold, so just burn up calories to "keep it warm". Yes, I realize being too hot is bad (e.g. a fever), but if you could somehow make the body just "waste" a little bit more energy without ALSO making you sweat, that would be really cool (pun intended).

Re:Waveforms?

[SeanBlader]

This would work well in an office where there isn't too much fat in the building.

Re:Waveforms?

[fuzzyfuzzyfungus]

It fails the 'without making you sweat' test, and it will continue to work up to (and past) the point of lethal hyperthermia, which is why nobody officially uses it any more; but a href="http://en.wikipedia.org/wiki/2,4-Dinitrophenol">2,4-Dinitrophenol does the trick.

The stuff craters the ATP synthesis efficiency of your mitochondria by allowing protons to pass through the membrane that is supposed to be maintaining the proton gradient for Oxidative phosphorylation. The energy that should have gone into producing ATP is then dissipated as waste heat. Obviously this isn't something you want to overdo (since either lack of ATP or excessive body temperature will do you a world of bad) and there are some concerns about the toxicity of the chemical outside of this particular effect; but sure burns off those excess calories.

Ten bucks a month?

[Anonymous Coward]

100 kWh is about $10-13. Something tells me outfitting an entire building with these devices would cost much more.

Re:Ten bucks a month?

[BronsCon]

for every 1 degree celcius... if that means the building can operate at 28C (roughly 82F) in the summer and 17C (roughly 62F) in the winter, rather than having to maintain 22C (roughly 72F) all year, that's 1000 kWh per month for the more extreme 2/3 of the year, or roughly 667 kWh on average. That's in the $60-90/mo range, $720-1080/yr, the kind of numbers that aren't huge but get your attention pretty damn quick if you're heating or cooling 20+k locations.

Re:Ten bucks a month?

[BronsCon]

Oh christ... I used fahrenheit for my cost savings calculations... it's more like $30-50/mo, or $360-600/yr. Still in the "you have my attention re: the 20+k buildings I have to heat and cool" range, though.

Re: Ten bucks a month?

[Anonymous Coward]

NASA? Is that you?

Re:Ten bucks a month?

[viperidaenz]

Unless you take into account you need to get one of these devices for every person in the building. There's 1000 people in the building I'm in right now. Its not even overly large.
You also need to power the devices too. Replace them when people break them and lose them, because they will.

Re:Ten bucks a month?

[BronsCon]

And, as a personal comfort device that you'll use in every building you enter, you buy your god damn own. Now I don't have to take that into account, thank you very much; nor do I need to power your devices for you.

that powersaving claim might want to come

[gl4ss]

that powersaving claim might want to come with specs about the bulding for it to make any sense at all.

Does it really cool you or give you just a cool feeling for a small while on your wrist? other is really easy to achieve and the other is really hard, edging on stillsuit territory. the heat has to go somewhere and I don't really envision carrying around 100watts+ worth of peltier cooling and a power source for that(with peltier efficiency at what, 10%? so I'd carry around a kw class power source?? or maybe just passive heatsinks attached to my shirt?? or maybe the system just sprinkles me with water and has a fan?).

unless they've made some mega-giga leap in TEC tech in which case fuck this usage scenario put them into the AC machines and save boatloads of money(though I really don't think they have developed a better heat pump because frankly they wouldn't announce it like this).

I think I'll just use the AC for now.

and an on topic public announcement: SPENDING THE WINTER IN THAILAND! SUCK IT BI**HES IN THE ARCTIC!!

Re:that powersaving claim might want to come

[jcochran]

Does it really cool you or give you just a cool feeling for a small while on your wrist?

Neither, it instead tricks your body into thinking the overall temperature is comfortable.

Re:that powersaving claim might want to come

[marcosdumay]

I tought somethng on the same lines, so I clicked on that link to RTFA. A mistake, obviously, since the article says nothing more than the summary.

The one thing that I could see there (but not read, of course), is that there are wires running from the bracelet, it's not self powered. Not very practical, but answers your questions.

Re:that powersaving claim might want to come

[gl4ss]

but I could take drugs for that.

Sure, I would pass out once the body got too warm and I had tricked my sweat glands to not work to keep me cool, so it would be rather pointless and maybe horrifying... which gets us to that the bracelet would have to either do that(block sweating) or not really work at all then.

I'm starting to just assume that the inside of it gets just cool for a second("waves") or two. then it equalizes again in temperature and does it again. the problem with that is of course that you can get someone to say that it makes them feel cool for one second. but in long range, 10+ minutes - you're just adding heat to the building and your wrist. seriously, a fucking battery operated handworn fan would do more actual cooling(and feel of it) than that, allowing the raising of the office temperature by a degree or two. or heck just install clothing rules that you must wear shorts and you can easily raise the temperature 3-7 degrees(hong kong is the craziest place. hot as fuck outside but every friggin shop and building is 20 something celsius or under, making it necessary, or rather enabling, the staff to wear full suits).

it's just that he actual idea of the device doesn't seem to be in realistic agreement with physics, energy use or well.. anything. it looks like a case of "hey we managed to build a circular tec so what are we gonna do with it??". how about using the tec to harvest the energy from the difference between outside air and the air exhausted from the building..

Re:that powersaving claim might want to come

[geekoid]

It's not about cooling, it's about comfort. This isn't for Arctic or Sahara survival use. You could lower the temperature by 1C or so and still be comfortable. The overall saving in that is pretty big.

Re:that powersaving claim might want to come

[icebike]

but I could take drugs for that.

Sure, I would pass out once the body got too warm and I had tricked my sweat glands to not work to keep me cool, so it would be rather pointless and maybe horrifying... which gets us to that the bracelet would have to either do that(block sweating) or not really work at all then.

Exactly. Our use a cap, or a sweater, or thinner clothing in hot weather.

Letting engineers regulate the human body so that the building can be run on less energy is the perfect definition of ASS BACKWARDS.

MIT should grow a Medical school instead of leaching off of Harvard. Perhaps then they might actually understand what they are messing with and perhaps grow to have a concept of ethics as well.

Re:that powersaving claim might want to come

[icebike]

The real article is here: http://web.mit.edu/newsoffice/2013/madmec-design-competition-1017.html

(Damn slashdot editors allowing blog hyping instead of linking to the actual sources!!!)

Close reading of that indicates this is just a huge trick played on the body's temperature regulation system.
There is no actual heating or cooling of the body. Its probably dangerous at some level, and the body would
also probably "learn" to ignore it.

Re:that powersaving claim might want to come

[marcosdumay]

And they beat a team that created an inexpensive solar cell and another that created a water filter that retains heavy metals, in a competition for sustainable technology, with that. Ok, it probably didn't consider how much the tech improved our footprint, just that it did improve, but even then, those other two are usefull.

Now that I ranted, it looks like a great experiment that could lead to some usefull data about our body's temperature control. It just doesn't look like a product.

Sounds dangerous

[punkr0x]

Isn't this basically tricking your body into thinking you're hotter or cooler than you really are? It might work temporarily but wearing this thing all day, every day sounds like it could mess up your body's ability to regulate your temperature.

Re:Sounds dangerous

[MightyYar]

You are supposed to take some ecstasy to balance things out. They have a pacifier version, too.

Re:Sounds dangerous

[DerekLyons]

Indeed - plus placebos generally don't work all that well when the person *knows* they're taking a placebo.

Re:Sounds dangerous

[unimind]

That's what immediately occured to me. I'm pretty sure our brain does important things with the information it gets about temperature (and everything else for that matter). If the brain's perception of body temperature is decoupled from actual body temp, I would think results might be a little unpredictable.

Re:Sounds dangerous

[unimind]

Actually, there have been some studies indicating placebos work regardless of whether the person knows it's a placebo.

Re:Sounds dangerous

[Anonymous Coward]

Placebos work really well for people who recognize the legitimacy of the placebo effect.

By far the most potent medicinal combination is to educate a person on the reality of the placebo effect, and then give them actual medicine which you mislead them to believe is a placebo.

I read theories that this is how Jesus actually brought people back from the dead.

Re:Sounds dangerous

[CastrTroy]

That's OK, we can't really feel temperature anyway. We really only feel the ability of objects to change the temperature of our skin. A piece of metal will feel colder than the air around it, even if it's the same temperature as the air itself.

Re:Sounds dangerous

[ColdWetDog]

Well, if I can trick my wife into thinking she is 'hotter' than she is, then we could well be on to something big.

Re:Sounds dangerous

[mattack2]

I thought that's why most people drank alcohol.

My main questions

[RevWaldo]

Does it keep you from sweating? Say when the humidity is 90-100% and perspiration does nothing but soak your clothes?

Wouldn't this kill your wrist after awhile? Especially if you're keyboarding? Perhaps an anklet?

.

Re:My main questions

[idontgno]

Perhaps an anklet?

Sure. They're coming up with an ankle version for the workplace environment. It comes attached to a 120 pound iron ball with a short segment of chain. You'll be cozy and secure at your galley oar ^w^w desk.

Re:My main questions

[sFurbo]

Its not an iron ball, it's just the battery. It has to be bigger because the feet are usually cooler than the rest of the body, so more cooling is needed to make a difference, and we all know how inefficient cooling is. Preliminary testing showed it to be highly effective at increasing employee efficiency*.

*Amount of time spent at desk was used as a proxy for employee efficiency.

Take my money please!

[Anonymous Coward]

If there is a kickstarter or something for this plz link!

jacket?

[Anonymous Coward]

I put on my jacket when I'm cold.

Sounds good but dodgy.

[Anonymous Coward]

I'd sure hope they would test this to the literal extremes where a person ends up being so cold or hot that they fall ill and potentially end up emergency cases.

If it could trick the body enough to make someone ill, then I would still consider it a huge success regardless because the system works and I am buying a million to put on all 1000 of my arms.

Mind you, it would likely be dangerous for me to put it on since I tend to sleep with windows open in south-west Scotland even at winter. Hey, I get laaaaazy at 4am.
But for general daytime activities where the temperature isn't OHGODMYBALLSAREINVERTED cold, it should work brilliantly at saving loads of power since comfort and temperature are two very different things to a lot of people.
Some people love the cold, some people love the heat, some people love both and hate being warm (me), some people like being hot in mornings and cold at night (me), warm & hot, blah blah etc. So if it could bring heating down to minimum safe temperatures legally allowed, that would be absolutely brilliant.

Heat allergies

[LongearedBat]

A few years ago my gf got an infection that now causes her to get rashes whenever she's warm, and being hot makes her skin terribly itchy. (Please don't bother with sordid jokes here. They're too easy, I'm tired and I'm actually being serious.) So far she's had to resort to taking antihistamines almost daily, and she's likely going to have to do that for the rest of her life.

This bracelet doesn't actually cover the body, so it's not actually making the skin cool. And I don't understand what the mean by waveforms across the skin. Does that mean it's telling the skin that it's cool/warm even when it's not?

So I'm wondering, could this be something to help her feel cool, and thereby less itchy, especially during summer?

Re:Heat allergies

[EvilSS]

This would not help your GF. However, to understand the principle, next time it's hot out, go outside and place an ice cube on the underside of your wrist.

Re:Heat allergies

[geekoid]

Maybe, but if it does it would be a pretty strong indicator that her issue may be in her head. That's not a judgement.

If it was an infection, she could actual be experiencing another bacterial infection of folicles. Antibiotics should help that.

http://www.ifd.org/protocols_bacterial.htm

Re:Heat allergies

[glitch!]

It sounds like her immune system is pretty messed up. I would make fixing that a priority so it doesn't get worse, or allow some future infection to blossom.

Somewhere, there must be a medical doctor that can figure out the cause, and get it fixed. At the very least, I would suggest vitamin D (2 x 5000IU) and vitamin C (2-10 grams, or as much as the body will take before laxative effect.) That should be safe and may give some relief.

Re:Heat allergies

[Grishnakh]

What I want to know is how much this actually affects the body's temperature. When you're really hot, one way to cool down is to put an ice cube on your forehead and on your neck, over your carotid arteries. This isn't just a trick; there's a lot of blood flowing through those spots on your body, so if you cool them down with an icecube, you're also cooling your blood, which of course cools your whole body because of the circulatory system. I imagine the same effect works with your wrist, but not nearly as effectively, since there isn't that much blood flowing near that point.

Of course, this won't help with skin temperature over the rest of your body, but you won't notice the skin being too hot or cold as badly if your blood supply is heated or cooled. I do wonder if long-term usage of a device like this might have negative effects on your body though.

Re:Heat allergies

[ColdWetDog]

Yep, probably in her head. Like in her hypothalamus.

And, more to the point, it might help the OP's GF's rash. Although some icy hot or an ice cube might be a good trial device and quite a bit smaller than the prototype.

Re:Heat allergies

[ColdWetDog]

Don't quit your day job just yet.

And you should come up with a new panacea. Both Vitamin D and Vitamin C have both been deprecated.

Re:Heat allergies

[EvilSS]

It won't, and neither will your ice cube (try it with a oral thermometer if you don't believe me). They lack the mass and cover too small of a surface area to make a dent your core body temp. If they could you probably wouldn't want it touching you, think about the amount of energy that would have to pass through a very small spot on your body to lower your body temp by even a fraction of a degree. That would not be comfortable at all.

Instead, your brain prioritizes extremes in sensory input like temperature (and pain, which is why topicals like bengay work on muscle pain). Some areas of the body are more sensitive than others (feet, forarms, etc) to temperature changes so they went with the wrist.

Overall I doubt there would be any negative effects. The hypothalamus itself contains the main thermoreceptors used to control body temp. It receives input from the skin, but it prioritizes itself first. Really, it's like the difference between wearing boots or flip flops or a short or long sleeve shirt. The only time this could become dangerous is if the person is already in or close to some kind of thermal crisis. This happens with the elderly some times when it's hot out. They will be in an room that is dangerously hot but they have a fan blowing on them so it blunts the body's signals that something is wrong. It "feels" a bit cooler but the air is too hot to actually cool the body, so they die.

Re:Heat allergies

[Anonymous Coward]

Yep. A few years ago she got a variant of herpes(?) that contained a receptor similar to that of platelets. Consequently her liver ate all her platelets. Yup, a count of 0, as in less than 1. (Healthy is 150-400.) She was in a pretty precarious state. But she survived and this is the lasting legacy of that time.

Re:Heat allergies

[Anonymous Coward]

I've never considered ice cubes on major arteries. I'll ask her to try it just to see what happens. But it's not the core temperature that is the problem, it's her skin temperature, so I doubt it would help.

Except it's pure trickery

[macraig]

... the team says the ultimate aim is to reduce the energy consumption of buildings, by cooling and heating the individual — not the building.

Bullshit. This device does nothing of the sort; instead it tricks the body into thinking the ambient temperature is just right when in fact it's not. Those nerves and body temperature regulation systems exist for a reason, and tricking and preempting them to save corporations money is sickening.

Re:Except it's pure trickery

[whois]

Maybe not. Your wrist has major arteries (veins? I dunno) close the the skin. Placing something to cool you there will cause the blood to carry it throughout your body.

I found out someone had made a peltier cooler for a person who can't sweat a while back. I wanted one so I google searched for it but apparently nobody makes them. Hopefully the MIT guys will actually come up with a cheap product for everyone.

Re:Except it's pure trickery

[macraig]

You'd have a distractingly hot/cold wrist at the very least if that had any hope of doing what you suggest. That's in any case not the goal of what is described.

Re:Except it's pure trickery

[geekoid]

Save everyone money, more inmportantly save energy.

If you could keep the temp of your home 2 degrees cooler or warmer, thus saving you money.

Re:Except it's pure trickery

[macraig]

You're missing the point: if the body is tricked - as this technique aims to do - into thinking the ambient temperature is tolerable when it's really not, that likely has a health effect. That part of the nervous system exists for a reason. As that ancient commercial declared, "it's not nice to fool Mother Nature!"

Re:Except it's pure trickery

[psithurism]

Nope, if you read the articles, it is trickery. To change your whole body temperature, you need an prolonged contact with a cold object to those veins. This thing is not warming or cooling you, it just fluctuates its temperature in such a way as to make you think you are warmer or colder than you really are.

This sounds dangerous to me.

From the articles linked it looks like they give you a quick pulse in the direction that you want to perceive and then gradually return the plate to normal so they can give you the next pulse, which they name "thermal waveforms."

Re:Except it's pure trickery

[mattack2]

That part of the nervous system exists for a reason.

You could say the same thing about hay fever or other allergies, yet in day to day life, they aren't actually saving people from anything.

Re:Except it's pure trickery

[macraig]

Allergies are a dysfunctional immune system response, not a normal constructive one. This device is not targeted at people with dysfunctional sensitivity to temperature, unless we conveniently reclassify any response to temperature as dysfunctional.

This will not work

[Anonymous Coward]

for very long. It may work in the short term but your body will adapt very quickly to these false readings. In short this is fucking retarded.

Not dorky enough

[OglinTatas]

I will stick with my beer hat with the clip-on fan and mister.

Payback 100 years

[Anonymous Coward]

100 KWh per month is about $10 in savings. Depending on how many employees there are and what the bracelets cost the payback time would be ridiculous.

Clothes?

[bananaquackmoo]

Am I missing something? Isn't this the exact same thing as putting on or taking off clothes?

Re:Clothes?

[Anonymous Coward]

Clothes are for your wife, this is what you get for your girlfriend.

Re:Clothes?

[Anonymous Coward]

No, clothes actually work in keeping you warmer or cooler. This thing just fakes it.

Really ridiculous

[Anonymous Coward]

This is really ridiculous. The heat flux from your body is about 150 watts. You can't apply even a small fraction of that through a small bracelet without exceeding the FDA guidelines. Plus a lot of us get drippy noses when the air temp goes down, a bracelet isn't going to help with that.

And it's not going to save any energy-- you're using electrical energy, the highest form, to make heat energy. The heat can be put into the ambient at more than twice that efficiency by using a gas-powered furnace.

Cheaper solution

[Hoi Polloi]

I have a cheaper system that involves a fan and a jacket.

Free alternative

[pla]

How about just letting most of us work from home, and only maintaining enough office space to host a handful of meeting/collaboration rooms? Bam, your whole "office building" just reduced to a 2nd story loft.

But hey, sure, let's instead try playing games with peoples' heads rather than address the real problem. And then the PHBs can ask themselves why the electric bill has actually gone up, when everyone starts keeping an electric space heater under their desk.

better and free solution

[Anonymous Coward]

stop being such a pussy

sometimes its hot, sometimes its cold, unless either of those conditions are causing health problems just train your body to ignore them

In Colorado that's actually true

[Anonymous Coward]

The state literally owns every drop of water within its borders, no matter where it is or what form it's in.

Cold feet

[PPH]

Anecdotal evidence: After having installed a radiant floor heating system, I made the following observation. If your feet are cold, you perceive the environment as being cold. And you turn up the heat. If your feet are warm, you can tolerate lower air temperatures.

This might be related to the rate of heat loss through contact. Where heat loss to air (via convection) is inefficient, loss through conduction is higher. Since the one point that is most often in contact with another surface is your feet, minimizing this loss path goes a long way to modifying perception.

I wonder how effective a thermoelectric bracelet will be if you perceive your arm as being warm but your feet are still cold.

Re:Cold feet

[CanHasDIY]

Anecdotal evidence: After having installed a radiant floor heating system, I made the following observation. If your feet are cold, you perceive the environment as being cold. And you turn up the heat. If your feet are warm, you can tolerate lower air temperatures.

Wrists, ankles, and neck.

These are the main points by which your body measures ambient temperature, and makes adjustments accordingly. Theoretically, if you were to wrap your wrists, ankles, and neck in some sort of warm material, you could very well walk out into near-zero temperatures otherwise naked, and not really feel the cold. Anecdotally, I tried this myself last winter (albeit with the addition of skivvies to avoid an indecent exposure charge), and I do recall noting that I didn't feel as cold as I should have.

Of course, it has to be said that 'feeling warm' will do absolutely nothing to prevent hypothermia and exposure.

Re:Cold feet

[Anonymous Coward]

Actually the body radiates lots of heat through big exposed veins in those areas. Wearing mittens, socks, a headband and a scarf WILL in fact decrease your loss of heat dramatically (> 50% iirc) and so stave off hypothermia for a long time - as long as your core temp is decent to begin with, that is.

pfft

[Anonymous Coward]

bowties make you cool, not bracelets

Congratulations MIT

[Anonymous Coward]

You just reinvented the CoolWare Personal Cooling System.

It's more of a technique than technology.

[denzacar]

Technology to do the same thing was invented a LONG time ago. Its called a sweater.

It's keeping one foot out from under the covers.

Re: It's more of a technique than technology.

[Anonymous Coward]

I think you're exactly correct with this analogy. They should market it this way.

Re: It's more of a technique than technology.

[icebike]

Except that actually works. Your foot can radiate enough excess heat to keep you from being too hot.

Re: It's more of a technique than technology.

[evil_aaronm]

Not mine, but I wish. I have bigger legs from years of cycling and running and I found that sleeping under the covers was a recipe for disaster: I got too hot, even in the winter. Instead, I sleep on top of the sheets, under a loose acrylic blanket that allows me to regulate how much of my legs are exposed - most of my lower body in the warmer months, and maybe my calves in the cooler months. Works well for me.

Will and Grace

[wisnoskij]

Did it like 15 years ago, which I assume was some sort of product placement.

RIP

[Anonymous Coward]

Any business that begrudges 100kWh for its employees' comfort ain't long for this world anyway.

Need cold?

[Anonymous Coward]

I once accidentally brushed against the arm of the wife of a student at a training institute. Her arm was like ice! I mentioned it to her husband and he agreed, she was cold to the touch all the time. If you live in Texas, you might look for such a woman to keep yourself cool. She would probably love being squeezed continuously.

physiological explanation is here

[Anonymous Coward]

It might work. Here is why: Go to youtube and search these four words,"cool hands better performance". Human physiology by big-time professor. Your brain, heart, and lungs need be kept at stable core temperature, but the rest of your body need not. Long lecture, but it's fascinating!

Re:physiological explanation is here

[PPH]

It'll never work. I agree with the conclusion, but I've been stuck with low metabolism thermostat whiners all my life. And I'm not just thinking of all the old geezers (I'm one now and I still like it cool). Younger people all seem to be handicapped when it comes to maintaining core temperature.

And then there's the poor air conditioning plant problem. An anecdote: Back when I worked at Boeing, I was located in a 1950's era building (one story, cinder block, no insulation) that was always kept at 78-80 deg F. All summer, all winter. Management stated that for energy savings, the AC set point had been set to 80F. And the resulting high temps were just due to the dissipation of people, PCs, lighting and whatnot. This argument stood until the Nisqually earthquake. Upon returning to work, the building was 68F in the morning (mid-winter) and rose to about 70F by the end of day. This apparently due to the gas boilers being taken off line until a safety inspection could be conducted. So it appeared that the building heat load was a bogus explanation.

After some time, I ran across one of the facilities HVAC people, related my observations to him and asked him what was with the 80F temps. He said that this was due to the building originally being equipped with single set point thermostats and management's insistence that air conditioning expenses be cut back by cranking the temp up. Management was too cheap (or stupid) to update the building controls and nobody dared tell a type A manager that his orders were a mistake and the heat would just come on. It was easier to burn extra fuel for 4 or 5 decades than risk the confrontation.

Another lost opportunity ...

[garyebickford]

Sigh. A few years ago (2005, actually) I played around with a Peltier junction body part warmer/cooler but did not carry it past a prototype. My idea was to take the place of hot/cold pads on sports injuries, help with backaches, etc. The idea was that this unit could replace both ice packs and hot pads, and even cycle between them, and provide the heat or cold at a precise temperature for a long time. I still have the prototype stuck in a box somewhere. It actually worked, but the hardest thing was getting rid of the excess heat when acting as an 'ice pack' - Peltier junctions aren't very efficient, so heat sinks and maybe fans are necessary, which reduces battery life, ...

Never work

[jtownatpunk.net]

Two reasons. The obvious one is that a lot of employees will balk at wearing the device.

The slightly less obvious one is the state of HVAC systems in many office buildings. The last building I worked in was straight out of Brazil. I had a thermostat on my wall that controlled the AC for my corner of my floor. Not the heat, tho. Every fall, people would lean in my office and ask me to turn up the heat. I'd explain over and over that I can only make it colder. They're welcome to look at my thermostat's setting and see that it's at its highest setting and can't go any higher. (The saddest part was that it was the same people every year. Like they didn't remember the last 4 winters.) I suspect that the heater's thermostat for our part of the building was the one that had been in the old conference room that was turned into an archive room. I know it controlled the AC for that room (and the adjacent server room) but I don't know about heat...or where it got moved when that room was renovated but the server room AC still worked so it must have gone somewhere. Maybe it was tossed on top of the ceiling tiles.

Anyway, my office had an AC thermostat and 5 different vents. 2 heat vents, 2 AC vents, and 1 that seemed to do nothing. It neither sucked nor blew. 1 AC vent was always blowing unless the heat was on. The other responded to my thermostat and blew cold air even if the heat was on. When the heat was working, I got hot air out of both my heater vents. They didn't appear to operate independently. And, yes, there were days when I'd sic the AC on the heater because the floor was roasting and nobody knew where the heater's thermostat was.

This is what happens to buildings after a few decades of rotating tenants. Each new tenant remodels. Walls go up, walls come down, vents move, controls move. You'll have to clean up all that crap before you can shave 1 degree off the heat or AC. Of course, after you've done that, you'll be saving enough money that it's not worth the hassle of convincing people to wear a geek bracelet.

Space Suit Application?

[Anonymous Coward]

I wonder if this could work in space suits?

A bold estimate indeed.

[Anonymous Coward]

Oh, from MIT? Then it must be important! Thence be sceeantists!

women & body temp

[Anonymous Coward]

maybe it will help with menopause & the debilitating hot flashes some women get ... where they're so hot they race to the bathroom to tear off their clothes several times an hour, and get no work done ... and to any idiot who thinks menopause is no big deal or lasts just a year, well, my secretary and I have both been in hell for about 9 years ... and none of the treatments help except hormones, which can cause strokes and cancer, and nearly killed a close friend ...